BGP-Based Congestion Signaling for Leaf-Spine Data Center Fabrics

This story was originally published on HackerNoon at: https://hackernoon.com/bgp-based-congestion-signaling-for-leaf-spine-data-center-fabrics. A proposal to use BGP as a fabric-wide congestion signaling mechanism, reducing AI workload tail latency and improving ECMP path balance. Check more stories related to tech-stories at: https://hackernoon.com/c/tech-stories. You can also check exclusive content about #bgp, #leaf-spine-networking, #data-center-networking, #ecmp, #ai-infrastructure, #network-engineering, #frrouting, #hackernoon-top-story, and more. This story was written by: @vijayananda. Learn more about this writer by checking @vijayananda's about page, and for more stories, please visit hackernoon.com. This article proposes BGP-CN, a congestion notification mechanism that uses BGP extended communities to distribute congestion information across leaf-spine data center fabrics. Rather than relying solely on local mechanisms such as ECN, PFC, and DCQCN, BGP-CN provides fabric-wide visibility, allowing switches to proactively adjust ECMP weights before congestion spreads. Prototype testing on a SONiC/FRR environment showed a 47% reduction in P99 tail latency and a 63% improvement in path utilization balance.